Those who claim everyone should outbreed, that wouldn't really change anything for the better, some would be more fit to survive than others, there would be a lot of variation, ranging from vigor to depression, all that should really matter is the health of the child, not breeding for particular features, which ultimately leads to unhealthy patterns. It's not a bad thing that birds of a feather flock together, and gradual "heirloom" style "open-pollination" based on the personalities, beliefs, goals, wants of the parents is a natural process, however breeding hybrids for the sake of breeding the world into equality will do everyone a huge disservice, same goes for linebreeding particular features at the cost of all else, both should be human rights violations if you ask me, this isn't some tavistock experiment, you get few chances in life, one should use them wisely, not because some cultish group of fanatics tell you that you must erase the world's cultures to start all over again, that in order to save it you must destroy the world...everybody has unique adaptations, in fact, we are evolving away from eachother, and not based on ethnicity, but on beliefs and lifestyles.
You're better off practicing the ideals without supporting the cause, because ultimately you're being played like pawns by people who don't give a damn about culture, they just want to dominate the planet, star system, galaxy, and whatever else they can form a parasitic relationship with.
Equality, sure...Liberty, in the right measure...Fraternity, whose and for what?
